use strict;
use warnings;
use Env qw/EGGSHELL/;
                                                                                
if (defined $EGGSHELL) {
    print "$EGGSHELL\n";
} else {
    print "EGGSHELL not defined in \%ENV\n";
}

##</code><code>##

[liverpole@golux ~]% perl envtest
EGGSHELL not defined in %ENV
[liverpole@golux ~]% setenv EGGSHELL 1379
[liverpole@golux ~]% perl envtest
1379